Power-Tool Cooling Apparatus

ABSTRACT

A power-tool cooling apparatus for a portable power tool comprises at least one cooling unit configured to generate a cooling fluid flow to cool a drive unit of the portable power tool, and at least one further cooling unit configured to generate a further cooling fluid flow. The at least one further cooling unit is designed to differ from the at least one cooling unit.

This application claims priority under 35 U.S.C. § 119 to patentapplication no. DE 10 2014 207 867.9, filed on Apr. 25, 2014 in Germany,the disclosure of which is incorporated herein by reference in itsentirety.

BACKGROUND

DE 10 2005 007 546 A1 has already disclosed a power-tool coolingapparatus for a portable power tool, wherein the power-tool coolingapparatus has a cooling unit which generates a cooling fluid flow andwhich serves for cooling a drive unit of the portable power tool, andsaid power-tool cooling apparatus has a passive cooling body which iscooled by means of the cooling fluid flow of the cooling unit.

Furthermore, DE 196 00 339 C1 has already disclosed a power-tool coolingapparatus for a portable power tool, wherein the power-tool coolingapparatus has a cooling unit which generates a cooling fluid flow andwhich serves for cooling a drive unit of the portable power tool. Inthis case, the cooling unit has an individual double fan impeller whichis provided for providing a cooling fluid flow for cooling the driveunit and a further cooling fluid flow for cooling a gearing unit of theportable power tool.

SUMMARY

The disclosure is based on a power-tool cooling apparatus for a portablepower tool, having at least one cooling unit which generates a coolingfluid flow and which serves at least for cooling a drive unit of theportable power tool.

It is proposed that the power-tool cooling apparatus comprises at leastone further cooling unit which serves for generating a further coolingfluid flow and which is designed to differ from the cooling unit forcooling the drive unit. Here, the expression “cooling unit” is intendedin particular to define a unit which is provided specifically forextracting and/or dissipating heat (thermal energy) from an elementand/or a unit, in particular by means of convection. “Provided” is to beunderstood in particular to mean specially configured and/or speciallyequipped. Where it is stated that an element and/or a unit is providedfor a particular function, this is to be understood in particular tomean that the element and/or the unit performs(s) and/or carries (carry)out said particular function in at least one usage and/or operatingstate. The cooling unit for cooling the drive unit is in particular inthe form of a main cooling unit. The cooling unit for cooling the driveunit is preferably in the form of a fan impeller unit. Thus, the coolingunit for cooling the drive unit is provided at least for generating acooling fluid flow which dissipates at least thermal energy from thedrive unit. Here, the cooling unit is preferably in the form of anactive cooling unit. It is however also conceivable for the cooling unitto be of some other configuration that appears expedient to a personskilled in the art, and to be configured for example as a cooling pumpunit, as a heat exchanger unit or the like.

The further cooling unit is in particular in the form of a secondarycooling unit. Here, the further cooling unit is preferably in the formof a fan impeller unit. Thus, the further cooling unit is preferably inthe form of an active cooling unit. It is however also conceivable forthe further cooling unit to be of some other configuration that appearsexpedient to a person skilled in the art, and to be configured forexample as a cooling pump unit, as a heat exchanger unit or the like.The further cooling unit is preferably provided at least for generatinga cooling fluid flow which dissipates at least thermal energy from atleast one unit of the portable power tool that preferably differs fromthe drive unit. That unit of the portable power tool to which thecooling fluid flow of the further cooling unit is assigned may in thiscase be in the form of an electronics unit, a percussive mechanism unit,a gearing unit, a control unit, an electric output unit or as some otherunit that appears expedient to a person skilled in the art. It ishowever also conceivable for the further cooling unit to be provided atleast for generating a cooling fluid flow which dissipates at leastthermal energy from the drive unit.

To make it possible to realize an advantageous level of cooling power,the cooling unit and/or the further cooling unit may each have at leastone additional, passive cooling body which is arranged on the unit towhich the respective cooling fluid flow of the cooling unit and/or ofthe further cooling unit is assigned. A “cooling body” is to beunderstood in particular to mean an element and/or a unit which are/isdesigned in targeted fashion for cooling further components, inparticular an electronics unit, and which are/is in particular inthermal and preferably direct mechanical contact with said components.For the dissipation of thermal energy to the surroundings, the coolingbody has in particular a surface area which is at least five times, inparticular at least 10 times, advantageously at least 20 times andparticularly advantageously at least 50 times larger than that of a cubeof identical volume, and comprises in particular at least 3, inparticular at least 10 and advantageously at least 20 cooling fins. Inthis case, a “cooling fin” is to be understood to mean an elongate, inparticular wall or bar-like component which is composed of aheat-conducting material and which is connected, in particularintegrally, to a main body of the cooling body at least at one location.A “main body of the cooling body” is to be understood in particular tomean a component which is composed of a heat-conducting material andwhich has at least one surface which is in thermal contact with acomponent to be cooled. It is preferably the case that the entirecooling body is composed of a heat-conducting material, and has inparticular a plate-shaped main body from which cooling fins extend,preferably only on one side of the main body. In particular, the coolingbody is configured especially for heat transfer to an air flow flowingalong at least one of the surfaces of the cooling body, and preferablyhas flow ducts through which an air flow for cooling the cooling bodycan be conducted. “Integrally” is to be understood in particular to meanat least cohesively connected, for example by way of a welding process,an adhesive bonding process, an injection process and/or some otherprocess that appears expedient to a person skilled in the art, and/or isadvantageously to be understood to mean formed in one piece, for exampleby production from one casting and/or by production in asingle-component or multi-component injection process, andadvantageously from a single blank.

The expression “designed to differ from” is to be understood here inparticular to mean a configuration of an element and/or of a unitrelative to a configuration of a further element and/or of a furtherunit, wherein the element and/or the unit are/is formed in particularseparately from the further element and/or further unit. Thus, thefurther cooling unit is preferably formed separately from the coolingunit. Here, the cooling unit may be in direct contact with the furthercooling unit, in particular for a drive of cooling fluid flow-generatingelements of the cooling unit and the further cooling unit. In analternative refinement of the power-tool cooling apparatus, the coolingunit has a dedicated unit for providing drive, and the further coolingunit likewise has a dedicated unit for providing drive. By means of theconfiguration according to the disclosure of the power-tool coolingapparatus, it is advantageously possible for an additional cooling fluidflow to be generated which can be used for intense cooling of componentsof the portable power tool. Furthermore, it can advantageously beensured, in the event of a failure of the cooling unit or of the furthercooling unit, that at least one cooling fluid flow for coolingcomponents of the portable power tool can be generated. Thus, it isadvantageously possible to ensure a high level of safety againstoverheating of components of the portable power tool.

It is furthermore proposed that the cooling unit has at least onecooling fluid flow-generating element which is formed separately from acooling fluid flow-generating element of the further cooling unit. Thecooling fluid flow-generating unit of the cooling unit is preferably inthe form of a fan impeller. It is however also conceivable for thecooling fluid flow-generating element of the cooling unit to be of someother configuration that appears expedient to a person skilled in theart, and to be configured for example as a cooling fluid pump element orthe like. The cooling fluid flow-generating element of the furthercooling unit is preferably in the form of a fan impeller. It is howeveralso conceivable for the cooling fluid flow-generating element of thefurther cooling unit to be of some other configuration that appearsexpedient to a person skilled in the art, and to be configured forexample as a cooling fluid pump element or the like. By means of theconfiguration according to the disclosure of the power-tool coolingapparatus, it is advantageously possible to provide two separate coolingfluid flows for cooling components of the portable power tool.Furthermore, it is advantageously possible for two separate cooling airducts to each be supplied with a cooling fluid flow. It is thus possibleto realize reliable cooling of components of the portable power tool.

It is also proposed that the cooling unit has at least one cooling fluidflow-generating element which, viewed along an axis of rotation of thecooling unit, is arranged so as to be spaced apart relative to a coolingfluid flow-generating element of the further cooling unit. “Arranged soas to be spaced apart” is to be understood here in particular to mean anarrangement of an element and/or of a unit relative to a further elementand/or a further unit, wherein a smallest spacing between the elementand/or the unit and the further element and/or the further unit is inparticular greater than 0.01 mm, preferably greater than 0.1 mm, andparticularly preferably greater than 1 mm, in particular viewed along adirection running at least substantially parallel to the axis ofrotation of the cooling unit. The cooling fluid flow-generating elementof the cooling unit and the cooling fluid flow-generating element of thefurther cooling unit are preferably arranged on a common drive axis. Thepower-tool cooling apparatus advantageously comprises at least onecooling fluid intake opening, which is assigned to the cooling unit, andat least one cooling fluid intake opening, which is assigned to thefurther cooling unit. By means of the configuration according to thedisclosure, it is thus advantageously possible to realize a delivery, inparticular an intake, of cooling fluid at two different positions. It isthus advantageously possible to realize an advantageous level of coolingpower for cooling components of the portable power tool. In particular,by virtue of in each case one cooling fluid intake opening beingassigned to the respective cooling unit, it is advantageously possiblefor a large total cooling fluid flow rate to be delivered for thepurposes of cooling components of the portable power tool.

It is furthermore proposed that the cooling unit and the further coolingunit can be driven by means of the drive unit. The drive unit ispreferably in the form of an electric motor. It is however alsoconceivable for the drive unit to be of some other configuration thatappears expedient to a person skilled in the art, and to be configuredfor example as a hybrid drive unit, as a combustion drive unit, as apneumatic drive unit, as a hydraulic drive unit or the like. By means ofthe configuration according to the disclosure of the power-tool coolingapparatus, it is advantageously possible to dispense with components fordriving the cooling unit and for driving the further cooling unit. It isfurthermore advantageously possible to realize a compact arrangement ofthe cooling unit and of the further cooling unit.

The power-tool cooling apparatus advantageously comprises at least onedrive power transmission unit which is provided for connecting thecooling unit in terms of drive to the further cooling unit. “Connectedin terms of drive” is to be understood here in particular to mean aconnection between at least two elements and/or at least two units, bymeans of which connection a transmission of drive power from one elementand/or one unit to the other element and/or the other unit can berealized, in particular by way of a mechanical connection of theelements and/or of the units. By means of the configuration according tothe disclosure, it is advantageously possible to attain a high level offlexibility with regard to the possibilities for arrangement of thecooling unit relative to the further cooling unit. Furthermore, drivepower of the drive unit can be utilized in an advantageous manner fordriving the cooling unit and the further cooling unit.

In one refinement of the power-tool cooling apparatus according to thedisclosure, the drive power transmission unit has at least one toothingfor connecting the cooling unit in terms of drive to the further coolingunit. Here, it is conceivable for the toothing to be formed as part of agearing unit of the drive power transmission unit, which gearing unit isprovided for realizing a connection between at least one drive element,in particular a drive shaft, of the cooling unit and a drive element, inparticular a drive shaft, of the further cooling unit. The toothing ispreferably in the form of an external toothing which is arranged on anouter circumference of the cooling fluid flow-generating element of thecooling unit and/or of the cooling fluid flow-generating element of thefurther cooling unit. Here, the toothing may be arranged on the coolingfluid flow-generating element of the cooling unit and/or on the coolingfluid flow-generating element of the further cooling unit by means of apositively locking, non-positively locking and/or cohesive connection.It is particularly preferable for a part of the toothing to be formedintegrally with the cooling fluid flow-generating element of the coolingunit, and a part of the toothing is preferably formed integrally withthe cooling fluid flow-generating element of the further cooling unit.By means of the configuration according to the disclosure, it ispossible in a structurally simple manner to realize a connection interms of drive between the cooling unit and the further cooling unit.

In a further refinement of the power-tool cooling apparatus according tothe disclosure, the drive power transmission unit has at least onewraparound element for connecting the cooling unit in terms of drive tothe further cooling unit. A “wraparound element” is to be understoodhere in particular to mean an element which, for a transmission of drivepower, is at least partially looped around a drive element, inparticular a drive shaft or the cooling fluid flow-generating element,and can thus be driven by the drive element. The wraparound element mayin this case be in the form of a belt (toothed belt, round belt, flatbelt or the like), a band, a chain or the like. By means of theconfiguration according to the disclosure of the power-tool coolingapparatus, it is advantageously possible to realize a smooth and quietdrive. Furthermore, it is advantageously possible for shocks in thedrive train to be dampened. Furthermore, substantially maintenance-freeoperation is advantageously possible.

It is furthermore proposed that the cooling unit has an axis of rotationwhich is arranged at least substantially parallel and offset withrespect to an axis of rotation of the further cooling unit. The coolingfluid flow-generating element of the cooling unit can preferably bedriven in rotation about the axis of rotation of the cooling unit. Thecooling fluid flow-generating element of the further cooling unit canpreferably be driven in rotation about the axis of rotation of thefurther cooling unit. “Substantially parallel” is to be understood herein particular to mean an orientation of a direction relative to areference direction, in particular in a plane, wherein the directiondeviates from the reference direction by in particular less than 8°,advantageously less than 5° and particularly advantageously less than2°. By means of the configuration according to the disclosure, it isadvantageously possible to realize a compact arrangement of the coolingunit and of the further cooling unit.

In an alternative refinement of the power-tool cooling apparatusaccording to the disclosure, it is proposed that the cooling unit has anaxis of rotation which is arranged at least substantially perpendicularto an axis of rotation of the further cooling unit. “Substantiallyperpendicular” is to be understood here in particular to mean anorientation of a direction and/or of an axis relative to a referencedirection and/or a reference axis, wherein the orientation of thedirection and/or of the axis at least differs from an at leastsubstantially parallel orientation with respect to the referencedirection and/or with respect to the reference axis, and is inparticular skewed or perpendicular with respect to the referencedirection and/or with respect to the reference axis. By means of theconfiguration according to the disclosure, it is advantageously possiblefor an available installation space of an existing portable power toolto be optimally utilized.

It is furthermore proposed that the further cooling unit, at least forcooling an electronics unit of the portable power tool, is formed atleast partially integrally with the electronics unit. The cooling unitis preferably at least partially integrated into a board or a printedcircuit board of the electronics unit. By means of the configuration ofthe power-tool cooling apparatus according to the disclosure, it isadvantageously possible to realize reliable cooling of the electronicsunit. The electronics unit can advantageously be reliably protectedagainst overheating. It is thus advantageously possible to attain a longservice life of the electronics unit.

Also proposed is a portable power tool having a power-tool coolingapparatus according to the disclosure. A “portable power tool” is to beunderstood here in particular to mean a power tool for machiningworkpieces, which power tool can be transported by an operator withoutthe use of a transportation machine. The portable power tool has inparticular a mass of less than 40 kg, preferably less than 10 kg andparticularly preferably less than 5 kg. In this case, the portable powertool may be in the form of a drilling and/or chipping hammer, apercussion drill, an electrically or pneumatically driven screwdriver, ajigsaw, a saber saw, an electrically or pneumatically driven planingmachine, an electrically or pneumatically driven grinding machine, orsome other portable power tool that appears expedient to a personskilled in the art. In this case, the portable power tool may be ofcorded or battery-operated design. The portable power tool is preferablyin the form of a handheld power tool. By means of the configurationaccording to the disclosure, it is possible to realize advantageouscooling of components of the portable power tool. In this way, it isadvantageously possible to realize a long service life of the portablepower tool.

It is furthermore proposed that the portable power tool comprises atleast one housing unit on which at least the cooling unit and thefurther cooling unit are arranged. It is preferable for the cooling unitand the further cooling unit to be arranged in the housing unit. Thus,the housing unit encloses in particular the cooling unit and the furthercooling unit. The housing unit may in this case be of a shell type ofconstruction, of pot type of construction or of a combined shell type ofconstruction and pot type of construction. It is particularly preferablythe case that the housing unit has at least two housing shell elementswhich are connected to one another, in particular detachably connectableto one another. By means of the configuration according to thedisclosure of the power tool, it is advantageously possible to realizereliable cooling of components of the portable power tool that arearranged in the housing unit.

It is furthermore proposed that the housing unit comprises at least oneair inlet region which is assigned at least to the further cooling unit,and comprises at least one further air inlet region which is assigned atleast to the cooling unit. In this way, it is advantageously possiblefor a large flow rate of ambient air to be delivered into the housingunit for cooling purposes. It is thus advantageously possible to realizeadequate cooling of components of the portable power tool.

It is furthermore proposed that the air inlet region and the further airinlet region are connected to one another by means of at least onecooling fluid duct of the housing unit. It is thus possible to realizeadvantageous delivery of cooling fluid for cooling purposes within thehousing unit.

The power-tool cooling apparatus according to the disclosure and/or theportable power tool according to the disclosure are/is not intended tobe restricted here to the usage and embodiment described above. Inparticular, in order to realize functionality described herein, thepower-tool cooling apparatus according to the disclosure and/or theportable power tool according to the disclosure may have a number ofindividual elements, components and units that deviates from a numberstated herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages will emerge from the following description of thefigures. The figures illustrates six embodiments of the disclosure. Thedrawing, the description and the claims contain numerous features incombination. A person skilled in the art will expediently also considerthe features individually and combine them to form meaningful furthercombinations.

In the figures:

FIG. 1 shows, in a schematic illustration, a portable power toolaccording to the disclosure having a power-tool cooling apparatusaccording to the disclosure,

FIG. 2 shows, in a schematic illustration, a detail view of thepower-tool cooling apparatus according to the disclosure,

FIG. 3 shows, in a schematic illustration, an alternative portable powertool according to the disclosure with an alternative power-tool coolingapparatus according to the disclosure, which comprises a drive powertransmission unit,

FIG. 4 shows, in a schematic illustration, a further alternativeportable power tool according to the disclosure with a furtheralternative power-tool cooling apparatus according to the disclosure,which comprises an alternative drive power transmission unit,

FIG. 5 shows, in a schematic illustration, a further alternativeportable power tool according to the disclosure with a furtheralternative power-tool cooling apparatus according to the disclosure,which comprises at least two separate cooling fluid ducts,

FIG. 6 shows, in a schematic illustration, a further alternativeportable power tool according to the disclosure with a furtheralternative power-tool cooling apparatus according to the disclosure,which is at least partially integrated into an electronics unit of theportable power tool, and

FIG. 7 shows, in a schematic illustration, a further alternativeportable power tool according to the disclosure with a furtheralternative power-tool cooling apparatus according to the disclosure,which is at least partially integrated into an electronics unit of theportable power tool.

DETAILED DESCRIPTION

FIG. 1 shows a portable power tool 12 a with a power-tool coolingapparatus 10 a. The portable power tool 12 a is in the form of adrilling and/or chipping hammer. In this case, the portable power tool12 a is in the form of a corded drilling and/or chipping hammer. It ishowever also conceivable for the portable power tool 12 a to be of someother configuration that appears expedient to a person skilled in theart, and to be configured for example as a battery-operated drillingand/or chipping hammer, a battery-operated drill driver or the like. Theportable power tool 12 a comprises at least one main handle 40 a and atleast one additional handle 42 a. The main handle 40 a is arranged on aside of the portable power tool 12 a which faces away from a toolreceptacle 44 a of the portable power tool 12 a. In this case, the mainhandle 40 a is mounted pivotably on a housing unit 38 a of the portablepower tool 12 a. A pivot axis of the main handle 40 a runs at leastsubstantially perpendicular to an axis of rotation 54 a of the toolreceptacle 44 a.

The housing unit 38 a is provided for accommodating at least one driveunit 16 a and at least one output unit 48 a of the portable power tool12 a. The output unit 48 a comprises a percussive mechanism unit 50 afor generating a percussive impulse. The drive unit 16 a and the outputunit 48 a interact, in a manner already known to a person skilled in theart, so as to exert a percussive impulse on the tool receptacle 44 aand/or on a machining tool 52 a arranged in the tool receptacle 44 a.The drive unit 16 a is in the form of an AC electric motor unit. In analternative configuration not illustrated in any more detail here, thedrive unit 16 a is in the form of an EC electric motor unit. It ishowever also conceivable for the drive unit 16 a to be of some otherconfiguration that appears expedient to a person skilled in the art; inparticular, in the case of a battery-operated configuration of theportable power tool 12 a, the drive unit 16 a is preferably in the formof a DC electric motor unit. A drive axis of rotation 56 a of the driveunit 16 a runs at least substantially perpendicular to the axis ofrotation 54 a of the tool receptacle 44 a. In this case, the drive axisof rotation 56 a of the drive unit 16 a runs at least substantiallyperpendicular to the axis of rotation 54 a of the tool receptacle 44 a.

The housing unit 38 a is of shell type of construction. Thus, thehousing unit 38 a comprises at least two housing shell elements 46 a, 64a (FIG. 2; only one of the housing shell elements 46 a is illustrated inFIG. 1) which, in a connecting plane, are detachably connectable to oneanother in a manner already known to a person skilled in the art. It ishowever also conceivable for the housing unit 38 a to be of pot type ofconstruction or to be of a combined shell type of construction and pottype of construction.

FIG. 2 shows a sectional view of the portable power tool 12 a along theline II-II in FIG. 1. The sectional view illustrates an arrangement ofthe power-tool cooling apparatus 10 a. The power-tool cooling apparatus10 a for the portable power tool 12 a comprises at least one coolingunit 14 a which generates a cooling fluid flow and which serves at leastfor cooling the drive unit 16 a of the portable power tool 12 a. Thecooling unit 14 a for cooling the drive unit 16 a forms, in this case, amain cooling unit. The cooling unit 14 a is in the form of a fanimpeller unit. Thus, the cooling unit 14 a comprises at least onecooling fluid flow-generating element 20 a which is in the form of a fanimpeller and which serves for generating a cooling fluid flow. It ishowever also conceivable for the cooling fluid flow-generating element20 a of the cooling unit 14 a for generating a cooling fluid flow to beof some other configuration that appears expedient to a person skilledin the art. To generate a cooling fluid flow, the cooling unit 14 a canbe driven by means of the drive unit 16 a. Here, the cooling fluidflow-generating element 20 a of the cooling unit 14 a is arranged on aside of the drive unit 16 a which faces the output unit 48 a. For thecooling fluid flow-generating element 20 a of the cooling unit 14 a tobe driven, the cooling fluid flow-generating element 20 a is arrangedrotationally conjointly on a drive element 58 a of the drive unit 16 a.The drive element 58 a is in the form of a drive shaft of the drive unit16 a. Thus, the cooling fluid flow-generating element 20 a of thecooling unit 14 a is connected rotationally conjointly to the driveshaft of the drive unit 16 a.

Furthermore, the power-tool cooling apparatus 10 a comprises at leastone further cooling unit 18 a which serves for generating a furthercooling fluid flow and which is designed so as to differ from thecooling unit 14 a for cooling the drive unit 16 a. Here, the furthercooling unit 18 a forms a secondary cooling unit which is provided inaddition to the cooling unit 14 a. The further cooling unit 18 a is inthe form of a fan impeller unit. Thus, the further cooling unit 18 acomprises at least one cooling fluid flow-generating element 22 a whichis in the form of a fan impeller and which serves for generating acooling fluid flow. It is however also conceivable for the cooling fluidflow generating element 22 a of the further cooling unit 18 a forgenerating a cooling fluid flow to be of some other configuration thatappears expedient to a person skilled in the art. To generate a furthercooling fluid flow, the further cooling unit 18 a can be driven by meansof the drive unit 16 a. Thus, the cooling unit 14 a and the furthercooling unit 18 a can be driven by means of the drive unit 16 a. Thecooling fluid flow-generating element 22 a of the further cooling unit18 a is in this case connected rotationally conjointly to the driveelement 58 a of the drive unit 16 a. Furthermore, the cooling fluidflow-generating element 22 a of the further cooling unit 18 a isarranged on a side of the drive unit 16 a which faces away from theoutput unit 48 a. Here, the cooling fluid flow-generating element 22 aof the further cooling unit 18 a is integrated into the drive unit 16.Thus, the cooling fluid flow-generating element 22 a of the furthercooling unit 18 a is arranged in a drive unit housing of the drive unit16 a.

The cooling fluid flow-generating element 22 a of the further coolingunit 18 a is formed separately from the cooling fluid flow-generatingelement 20 a of the cooling unit 14 a. Thus, the cooling unit 14 a hasat least one cooling fluid flow-generating element 20 a which is formedseparately from a cooling fluid flow-generating element 22 a of thefurther cooling unit 18 a. Furthermore, the cooling fluidflow-generating element 22 a of the further cooling unit 18 a isarranged on the drive element 58 a of the drive unit 16 a so as to bespaced apart relative to the cooling fluid flow-generating element 20 aof the cooling unit 14 a. Here, the cooling fluid flow-generatingelement 22 a of the further cooling unit 18 a is arranged so as to bespaced apart relative to the cooling fluid flow-generating element 20 aof the cooling unit 14 a as viewed along an axis of rotation 24 a of thecooling unit 14 a. Thus, the cooling unit 14 a has at least one coolingfluid flow-generating element 20 a which, as viewed along an axis ofrotation 24 a of the cooling unit 14 a, is arranged so as to be spacedapart relative to a cooling fluid flow-generating element 22 a of thefurther cooling unit 18 a. Thus, the cooling unit 14 a and the furthercooling unit 18 a are arranged so as to be spaced apart axially relativeto one another. The axis of rotation 24 a of the cooling unit 14 a isarranged coaxially with respect to the drive axis of rotation 56 a ofthe drive unit 16 a. Here, the drive axis of rotation 56 a of the driveunit 16 a forms the axis of rotation 24 a of the cooling unit 14 a,about which the cooling fluid flow-generating element 20 a of thecooling unit 14 a can be driven in rotation. Furthermore, the drive axisof rotation 56 a of the drive unit 16 a forms an axis of rotation 32 aof the further cooling unit 18 a, about which the cooling fluidflow-generating element 22 a of the further cooling unit 18 a can bedriven in rotation. The axis of rotation 24 a of the cooling unit 14 ais thus oriented coaxially with respect to the axis of rotation 32 a ofthe further cooling unit 18 a. Owing to the arrangement of the coolingfluid flow-generating element 20 a of the cooling unit 14 a and of thecooling fluid flow-generating element 22 a of the further cooling unit18 a on the drive element 58 a of the drive unit 16 a, the drive axis ofrotation 56 a forms a drive power transmission unit which is providedfor connecting the cooling unit 14 a in terms of drive to the furthercooling unit 18 a.

The cooling unit 14 a and the further cooling unit 18 a are arranged onthe housing unit 38 a of the portable power tool 12 a. In this case, thecooling unit 14 a and the further cooling unit 18 a are arranged in thehousing unit 38 a of the portable power tool 12 a. Thus, the housingshell elements 46 a of the housing unit 38 a surround the cooling unit14 a and the further cooling unit 18 a. Here, the housing unit 38 acomprises at least one air inlet region 60 a for enabling cooling fluidflows to be generated by means of the cooling unit 14 a and the furthercooling unit 18 a. The air inlet region 60 a comprises at least one airinlet opening 62 a. Overall, the air inlet region 60 a has amultiplicity of inlet openings 62 a which are configured in a manneralready known to a person skilled in the art. The air inlet region 60 ais in this case arranged on the housing unit 38 a at a side of the driveunit 16 a which faces away from the output unit 48 a. By means of thefurther cooling unit 18 a, in particular by virtue of the cooling fluidflow-generating element 22 a of the further cooling unit 18 a beingdriven in rotation, ambient air can be delivered through the air inletopenings 62 a of the air inlet region 60 a into the housing unit 38 a.Thus, a sub-region of the housing unit 38 a extending from the air inletregion 60 a at least to the drive unit 16 a forms a first cooling fluidduct of the power-tool cooling apparatus 10 a. An electronics unit 34 aof the portable power tool 12 a is arranged in said sub-region of thehousing unit 38 a and thus in the first cooling fluid duct. Thus, theelectronics unit 34 a is cooled owing to delivery of ambient air bymeans of the further cooling unit 18 a.

Owing to the arrangement of the further cooling unit 18 a within thedrive unit housing of the drive unit 16 a, the ambient air drawn intothe housing unit 38 a through the air inlet openings 62 a of the airinlet region 60 a can be delivered into the drive unit housing of thedrive unit 16 a. In this way, it is advantageously possible for coolingof the drive unit 16 a, in particular of a commutator of the drive unit16 a, to be ensured in targeted fashion. The drive unit housing of thedrive unit 16 a comprises at least one cooling air outlet openingthrough which ambient air delivered by means of the further cooling unit18 a can emerge from the drive unit housing of the drive unit 16 a. Thecooling air outlet opening of the drive unit housing of the drive unit16 a is in this case directly connected to a further cooling fluid ductof the power-tool cooling apparatus 10 a. The further cooling fluid ductof the power-tool cooling apparatus 10 a extends in this case at leastfrom a further air inlet region 66 a of the housing unit 38 a to an airoutlet region 70 a of the housing unit 38 a. The first cooling fluidduct and the further cooling fluid duct may in this case be formeddirectly adjacent to one another. Thus, the first air inlet region 60 aand the further air inlet region 68 a are connected to one another bymeans of at least one cooling fluid duct of the housing unit 38 a. It ishowever also conceivable for the first cooling fluid duct and thefurther cooling fluid duct to be formed spatially separately from oneanother and to each extend separately as far as the air outlet region 70a of the housing unit 38 a. The further air inlet region 66 a of thehousing unit 38 a comprises at least one air inlet opening 68 a.Altogether, the further air inlet region 66 a has a multiplicity of airinlet openings 68 a which are configured in a manner already known to aperson skilled in the art. The further air inlet region 66 a is arrangedso as to be spaced apart relative to the air inlet region 60 a. In thiscase, the further air inlet region 66 a is arranged so as to be spacedapart relative to the air inlet region 60 a as viewed along the driveaxis of rotation 56 a. The air outlet region 70 a of the housing unit 38a comprises at least one air outlet opening 72 a. Altogether, thefurther air inlet region 66 a has a multiplicity of air inlet openings68 a, which are configured in a manner already known to a person skilledin the art. The air outlet region 70 a is arranged so as to be spacedapart relative to the further air inlet region 66 a. Here, the airoutlet region 70 a is arranged so as to be spaced apart relative to thefurther air inlet region 66 a as viewed along the drive axis of rotation56 a. Thus, the housing unit 38 a comprises at least one air inletregion 60 a, to which at least the further cooling unit 18 a isassigned, and at least one further air inlet region 68 a, to which atleast the cooling unit 14 a is assigned.

By means of the cooling unit 14 a, in particular by virtue of thecooling fluid flow-generating element 20 a of the cooling unit 14 abeing driven in rotation, ambient air can be delivered through the airinlet openings 68 a of the further air inlet region 66 a into thehousing unit 38 a, which ambient air can be mixed by means of theambient air which emerges from the drive unit housing of the drive unit16 a and which has previously been delivered by means of the furthercooling unit 18 a. It is thus advantageously possible for a high totalflow rate of ambient air, which can be delivered through the housingunit 38 a for cooling purposes, to be delivered by means of the coolingunit 14 a and the further cooling unit 18 a; this can be utilized foradvantageous cooling of components of the portable power tool 12 a thatare arranged within the housing unit 38 a, for example the drive unit 16a, the electronics unit 64 a, the percussive mechanism unit 50 a or thelike.

FIGS. 3 to 7 show further embodiments of the disclosure. The followingdescriptions and the drawings are restricted substantially to thedifferences between the embodiments, wherein, with regard to componentsof identical designation, in particular with regard to components withidentical reference signs, reference may basically also be made to thedrawings and/or the description of the other embodiments, in particularFIGS. 1 and 2. For distinction between the embodiments, the alphabeticcharacter a is provided as an affix to the reference signs of theembodiment in FIGS. 1 and 2. In the embodiments of FIGS. 3 to 7, thealphabetic character a has been replaced by the alphabetic characters bto f.

FIG. 3 shows an alternative portable power tool 12 b with an alternativepower-tool cooling apparatus 10 b. The portable power tool 12 b is inthe form of a percussion drill. It is however also conceivable for theportable power tool 12 b to be of some other configuration that appearsexpedient to a person skilled in the art. The portable power tool 12 bhas a housing unit 38 b which is provided for surrounding a drive unit16 b and an output unit 48 b. The housing unit 38 b is of shell type ofconstruction. Thus, the housing unit 38 b comprises at least two housingshell elements 46 b (only one of the housing shell elements 46 b isillustrated in FIG. 3) which, in a connecting plane, are detachablyconnectable to one another in a manner already known to a person skilledin the art. It is however also conceivable for the housing unit 38 b tobe of pot type of construction or to be of a combined shell type ofconstruction and pot type of construction. The portable power tool 12 bfurthermore comprises a main handle 40 b which is formed integrally withthe housing unit 38 b. Furthermore, the portable power tool 12 bcomprises an additional handle 42 b that can be arranged detachably onthe housing unit 38 b.

The output unit 48 b comprises a percussive mechanism unit 50 b forgenerating a percussive impulse. The drive unit 16 b and the output unit48 b interact, in a manner already known to a person skilled in the art,so as to exert a percussive impulse on a tool receptacle 44 b of theportable power tool 12 b and/or on a machining tool (not illustrated inany more detail here) arranged in the tool receptacle 44 b. The driveunit 16 b is in the form of a DC electric motor unit. In an alternativeconfiguration not illustrated in any more detail here, the drive unit 16b is in the form of an EC electric motor unit. It is however alsoconceivable for the drive unit 16 b to be of some other configurationthat appears expedient to a person skilled in the art. A drive axis ofrotation 56 b of the drive unit 16 b runs at least substantiallyparallel to an axis of rotation 54 b of the tool receptacle 44 b.

The power-tool cooling apparatus 10 b illustrated in FIG. 3 for theportable power tool 12 b has at least one cooling unit 14 b whichgenerates a cooling fluid flow and which serves at least for cooling thedrive unit 16 b of the portable power tool 12 b. Furthermore, thepower-tool cooling apparatus 10 b has at least one further cooling unit18 b which serves for generating a further cooling fluid flow and whichis designed so as to differ from the cooling unit 14 b for cooling thedrive unit 16 b. The cooling unit 14 b and the further cooling unit 18 bare arranged on the housing unit 38 b. In this case, the cooling unit 14b and the further cooling unit 18 b are arranged in the housing unit 38b. The further cooling unit 18 b is provided in particular for coolingan electronics unit 34 b, arranged in the housing unit 38 b, of theportable power tool 12 b.

The cooling unit 14 b and the further cooling unit 18 b are each in theform of fan impeller units. In this case, the cooling unit 14 b has atleast one cooling fluid flow-generating element 20 b which is formedseparately from a cooling fluid flow-generating element 22 b of thefurther cooling unit 18 b. The cooling fluid flow-generating element 20b of the cooling unit 14 b and the cooling fluid flow-generating element22 b of the further cooling unit 18 b are each in the form of fanimpellers. In this case, the cooling fluid flow-generating element 20 bof the cooling unit 14 b and the cooling fluid flow-generating element22 b of the further cooling unit 18 b are arranged so as to be spacedapart relative to one another as viewed along a at least substantiallyperpendicular to a drive axis of rotation 56 b of the drive unit 16 b.The cooling unit 14 b and the further cooling unit 18 b can be driven bymeans of the drive unit 16 b. In this case, the cooling fluidflow-generating element 20 b of the cooling unit 14 b is connectedrotationally conjointly to a drive element 58 b of the drive unit 16 b.Thus, the drive axis of rotation 56 b of the drive unit 16 b forms anaxis of rotation 24 b of the cooling unit 14 b.

Furthermore, the power-tool cooling apparatus 10 b comprises at leastone drive power transmission unit 26 b which is provided for connectingthe cooling unit 14 b in terms of drive to the further cooling unit 18b. In this case, the drive power transmission unit 26 b has at least onewraparound element 30 b for connecting the cooling unit 14 b in terms ofdrive to the further cooling unit 18 b. For a connection in terms ofdrive between the cooling unit 14 b and the further cooling unit 18 b,the wraparound element 30 b is looped at least partially around thecooling fluid flow-generating element 20 b of the cooling unit 14 b andthe cooling fluid flow-generating element 22 b of the further coolingunit 18 b. Thus, the cooling fluid flow-generating element 20 b of thecooling unit 14 b and the cooling fluid flow-generating element 22 b ofthe further cooling unit 18 b are connected to one another in terms ofdrive by means of the wraparound element 30 b. The cooling unit 14 b hasthe axis of rotation 24 b, which is arranged at least substantiallyparallel and offset with respect to an axis of rotation 32 b of thefurther cooling unit 18 b. With regard to further features and functionsof the power-tool cooling apparatus 10 b illustrated in FIG. 3,reference may be made to the description of the power-tool coolingapparatus 10 a described in FIGS. 1 and 2.

FIG. 4 shows an alternative portable power tool 12 c with an alternativepower-tool cooling apparatus 10 c, which comprises at least one coolingunit 14 c which generates a cooling fluid flow and which serves at leastfor cooling a drive unit 16 c of the portable power tool 12 c, and atleast one further cooling unit 18 c which serves for generating afurther cooling fluid flow and which is designed to differ from thecooling unit 14 c for cooling the drive unit 16 c. The portable powertool 12 c illustrated in FIG. 4 is of at least substantially analogousconfiguration to the portable power tool 12 b described in FIG. 3. Thepower-tool cooling apparatus 10 c illustrated in FIG. 4 is of an atleast substantially analogous configuration to the power-tool coolingapparatus 10 b illustrated in FIG. 3. By contrast to the power-toolcooling apparatus 10 b illustrated in FIG. 3, the power-tool coolingapparatus 10 c illustrated in FIG. 4 has at least one drive powertransmission unit 26 c which is provided for connecting the cooling unit14 c in terms of drive to the further cooling unit 18 c, wherein thedrive power transmission unit 26 c has at least one toothing 28 c forconnecting the cooling unit 14 c in terms of drive to the furthercooling unit 18 c. In this case, the drive power transmission unit 26 ccomprises at least one toothing element 74 c which is formed integrallywith a gearing element 78 c of an output unit 48 c of the portable powertool 12 c. The gearing element 78 c is in the form of a planetarygearing element, in particular in the form of an internal gear, of theoutput unit 48 c, which is at least partially in the form of a planetarygearing. Furthermore, the drive power transmission unit 26 c comprisesat least one further toothing element 76 c which is formed integrallywith a cooling fluid flow-generating element 22 c of the further coolingunit 18 c. The further toothing element 76 c is arranged on an outercircumference of the cooling fluid flow-generating element 22 c, whichis in the form of a fan impeller, of the further cooling unit 18 c. Inthis case, for the rotational drive of the further cooling unit 18 c, inparticular of the cooling fluid flow-generating element 22 c of thefurther cooling unit 18 c, the toothing element 74 c meshes with thefurther toothing element 76 c. With regard to further features andfunctions of the power-tool cooling apparatus 10 c illustrated in FIG.4, reference may be made to the description of the power-tool coolingapparatus 10 a described in FIGS. 1 and 2.

FIG. 5 shows an alternative portable power tool 12 d with an alternativepower-tool cooling apparatus 10 d, which comprises at least one coolingunit 14 d which generates a cooling fluid flow and which serves at leastfor cooling a drive unit 16 d of the portable power tool 12 d, and atleast one further cooling unit 18 d which serves for generating afurther cooling fluid flow and which is designed to differ from thecooling unit 14 d for cooling the drive unit 16 d. The portable powertool 12 d illustrated in FIG. 5 is of at least substantially analogousconfiguration to the portable power tool 12 b described in FIG. 3. Thepower-tool cooling apparatus 10 d illustrated in FIG. 5 is of an atleast substantially analogous configuration to the power-tool coolingapparatus 10 b illustrated in FIG. 3. By contrast to the power-toolcooling apparatus 10 b illustrated in FIG. 3, the power-tool coolingapparatus 10 d illustrated in FIG. 5 has at least one drive powertransmission unit 26 d which is provided for connecting the cooling unit14 d in terms of drive to the further cooling unit 18 d, wherein thedrive power transmission unit 26 d has at least one toothing 28 d forconnecting the cooling unit 14 d in terms of drive to the furthercooling unit 18 d. In this case, the drive power transmission unit 26 dcomprises at least one toothing element 74 d which is formed integrallywith a cooling fluid flow-generating element 20 d of the cooling unit 14d. The toothing element 74 d is arranged on an outer circumference ofthe cooling fluid flow-generating element 20 d, which is in the form ofa fan impeller, of the cooling unit 14 d. Furthermore, the drive powertransmission unit 26 d comprises at least one further toothing element76 d which is formed integrally with a cooling fluid flow-generatingelement 22 d of the further cooling unit 18 d. The further toothingelement 76 d is arranged on an outer circumference of the cooling fluidflow-generating element 22 d, which is in the form of a fan impeller, ofthe further cooling unit 18 d. In this case, for the rotational drive ofthe further cooling unit 18 d, in particular of the cooling fluidflow-generating element 22 d of the further cooling unit 18 d, thetoothing element 74 d meshes with the further toothing element 76 d. Thecooling unit 14 d is arranged in a first cooling fluid duct of thepower-tool cooling apparatus 10 d. The further cooling unit 18 d isarranged in a further cooling fluid duct of the power-tool coolingapparatus 10 d. In this case, the first cooling fluid duct and thefurther cooling fluid duct are arranged spatially separately from oneanother in the housing unit 38 d. With regard to further features andfunctions of the power-tool cooling apparatus 10 d illustrated in FIG.5, reference may be made to the description of the power-tool coolingapparatus 10 a described in FIGS. 1 and 2.

FIG. 6 shows an alternative portable power tool 12 e with an alternativepower-tool cooling apparatus 10 e, which comprises at least one coolingunit 14 e which generates a cooling fluid flow and which serves at leastfor cooling a drive unit 16 e of the portable power tool 12 e, and atleast one further cooling unit 18 e which serves for generating afurther cooling fluid flow and which is designed to differ from thecooling unit 14 e for cooling the drive unit 16 e. The portable powertool 12 e illustrated in FIG. 6 is of at least substantially analogousconfiguration to the portable power tool 12 b described in FIG. 3. Thepower-tool cooling apparatus 10 e illustrated in FIG. 6 is of an atleast substantially analogous configuration to the power-tool coolingapparatus 10 b illustrated in FIG. 3. By contrast to the power-toolcooling apparatus 10 b illustrated in FIG. 3, the power-tool coolingapparatus 10 e illustrated in FIG. 6 has the further cooling unit 18 ewhich, at least for cooling an electronics unit 34 e of the portablepower tool 12 e, is formed at least partially integrally with theelectronics unit 34 e. In this case, the electronics unit 34 e has atleast one cooling unit drive unit 80 e which is provided for driving thefurther cooling unit 18 e. The cooling unit drive unit 80 e is formedseparately from the drive unit 16 e of the portable power tool 12 e. Inthis case, the cooling unit drive unit 80 e is in the form of anelectric motor unit. It is however also conceivable for the cooling unitdrive unit 80 e to be of some other configuration that appears expedientto a person skilled in the art. A cooling fluid flow-generating element22 e of the further cooling unit 18 e is arranged rotationallyconjointly with a drive element 82 e of the cooling unit drive unit 80e. The cooling fluid flow-generating element 22 e of the further coolingunit 18 e is in the form of a fan impeller. In this case, the coolingfluid flow-generating element 22 e of the further cooling unit 18 e canbe driven in rotation by means of the cooling unit drive unit 80 e.

The cooling unit 14 e, in particular a cooling fluid flow-generatingelement 20 e of the cooling unit 14 e, has an axis of rotation 24 ewhich is arranged so as to be at least substantially parallel and offsetwith respect to an axis of rotation 32 e of the further cooling unit 18e, in particular of the cooling fluid flow-generating element 22 e ofthe further cooling unit 18 e. Thus, the cooling unit 14 e is arrangedin the housing unit 38 e so as to be spaced apart relative to thefurther cooling unit 18 e. With regard to further features and functionsof the power-tool cooling apparatus 10 e illustrated in FIG. 6,reference may be made to the description of the power-tool coolingapparatus 10 a described in FIGS. 1 and 2.

FIG. 7 shows an alternative portable power tool 12 f with an alternativepower-tool cooling apparatus 10 f, which comprises at least one coolingunit 14 f which generates a cooling fluid flow and which serves at leastfor cooling a drive unit 16 f of the portable power tool 12 f, and atleast one further cooling unit 18 f which serves for generating afurther cooling fluid flow and which is designed to differ from thecooling unit 14 f for cooling the drive unit 16 f. The portable powertool 12 f illustrated in FIG. 7 is of at least substantially analogousconfiguration to the portable power tool 12 b described in FIG. 3. Thepower-tool cooling apparatus 10 f illustrated in FIG. 7 is of an atleast substantially analogous configuration to the power-tool coolingapparatus 10 e illustrated in FIG. 6. By contrast to the power-toolcooling apparatus 10 e illustrated in FIG. 6, the power-tool coolingapparatus 10 f illustrated in FIG. 7 has the cooling unit 14 f, whichhas an axis of rotation 24 f which is arranged at least substantiallyperpendicular to an axis of rotation 32 f of the further cooling unit 18f. Furthermore, the power-tool cooling apparatus 10 f has at least oneadditional cooling unit 84 f which is provided for generating a coolingfluid flow. The additional cooling unit 84 f is in this case formedseparately from the cooling unit 14 f and from the further cooling unit18 f. The additional cooling unit 84 f is integrated into a furtherelectronics unit 36 f of the portable power tool 12 f. In this case, theadditional cooling unit 84 f is in the form of a fan impeller unit. Itis however also conceivable for the additional cooling unit 84 f to beof some other configuration that appears expedient to a person skilledin the art. The further electronics unit 36 f of the portable power tool12 f is arranged in a main handle 40 f of the portable power tool 12 f.Thus, at least one air inlet region 60 f of a housing unit 38 f of theportable power tool 12 f is arranged in the main handle 40 f. An airoutlet region 70 f of the housing unit 38 f is connected to the airinlet region 60 f by means of a first cooling fluid duct of thepower-tool cooling apparatus 10 f. In this case, at least the furthercooling unit 18 f and the additional cooling unit 84 f are arranged inthe first cooling fluid duct. The additional cooling unit 84 f isprovided for delivering ambient air into the housing unit 38 f throughair inlet openings 62 f of the air inlet region 60 f. The furthercooling unit 18 f is provided for delivering the ambient air, which hasbeen delivered into the housing unit 38 f by means of the additionalcooling unit 84 f, out of the housing unit 38 f through air outletopenings 72 f of the air outlet region 70 f. With regard to furtherfeatures and functions of the power-tool cooling apparatus 10 fillustrated in FIG. 7, reference may be made to the description of thepower-tool cooling apparatus 10 a described in FIGS. 1 and 2.

1-14. (canceled)
 15. A power-tool cooling apparatus for a portablepower-tool, comprising: a first fan configured to generate a firstcooling fluid flow to cool a drive unit of the portable power-tool; asecond fan configured to generate a second cooling fluid flow to cool afirst electronics unit of the portable power-tool; and a third fanconfigured to generate a third cooling fluid flow to cool a secondelectronics unit of the portable power-tool, wherein the third coolingfluid flow supplies a first cooling fluid to the first cooling fluidflow.
 16. The power-tool cooling apparatus according to claim 15,further comprising: at least one housing unit defining at least in parta cooling fluid duct configured to direct at least a portion of thethird fluid flow from the third fan to the drive unit.
 17. Thepower-tool cooling apparatus according to claim 16, wherein: the atleast one housing defines a first inlet region configured to supplysecond cooling fluid to the second fan; and the at least one housingdefines a second inlet region configured to supply third cooling fluidto the third fan.
 18. The power-tool cooling apparatus according toclaim 17, wherein: the at least one housing defines a handle: and thesecond inlet region is defined in the handle.
 19. The power-tool coolingapparatus according to claim 18, wherein the at least one housing isconfigured such that all of the third cooling fluid is directed out ofthe handle toward the drive unit and the first electronics unit.
 20. Thepower-tool cooling apparatus according to claim 15, wherein: the firstfan includes at least one first fan impeller; the second fan includes atleast one second fan impeller; the third fan includes at least one thirdfan impeller; and each of the at least one first fan impeller, the atleast one second fan impeller, and the at least one third fan impelleris configured to be separate from the other of the at least one firstfan impeller, the at least one second fan impeller, and the at least onethird fan impeller.
 21. The power-tool cooling apparatus according toclaim 20, wherein the at least one first fan impeller is spaced apartfrom the at least one second fan impeller with respect to an axis ofrotation defined by the first fan.
 22. The power-tool cooling apparatusaccording to claim 21, further comprising: at least one housing unitdefining at least in part a cooling fluid duct configured to direct atleast a portion of the third fluid flow from the third fan to the driveunit.
 23. The power-tool cooling apparatus according to claim 22,wherein: the at least one housing defines a first inlet regionconfigured to supply second cooling fluid to the second fan; and the atleast one housing defines a second inlet region configured to supplythird cooling fluid to the third fan.
 24. The power-tool coolingapparatus according to claim 23, wherein: the at least one housingdefines a handle: and the second inlet region is defined in the handle.25. The power-tool cooling apparatus according to claim 24, wherein theat least one housing is configured such that all of the third coolingfluid is directed out of the handle toward the drive unit and the firstelectronics unit.
 26. The power-tool cooling apparatus according toclaim 15, wherein the first fan defines an axis of rotation that is atleast substantially perpendicular to an axis of rotation defined by thesecond fan.
 27. The power-tool cooling apparatus according to claim 26,further comprising: at least one housing unit defining at least in parta cooling fluid duct configured to direct at least a portion of thethird fluid flow from the third fan to the drive unit.
 28. Thepower-tool cooling apparatus according to claim 27, wherein: the atleast one housing defines a first inlet region configured to supplysecond cooling fluid to the second fan; and the at least one housingdefines a second inlet region configured to supply third cooling fluidto the third fan.
 29. The power-tool cooling apparatus according toclaim 28, wherein: the at least one housing defines a handle: and thesecond inlet region is defined in the handle.
 30. The power-tool coolingapparatus according to claim 29, wherein the at least one housing isconfigured such that all of the third cooling fluid is directed out ofthe handle toward the drive unit and the first electronics unit.
 31. Thepower-tool cooling apparatus according to claim 15, wherein the thirdfan is formed integrally with the second electronics unit of theportable power tool.
 32. The power-tool cooling apparatus according toclaim 2316, further comprising: at least one housing unit defining atleast in part a cooling fluid duct configured to direct at least aportion of the third fluid flow from the third fan to the drive unit.33. The power-tool cooling apparatus according to claim 32, wherein: theat least one housing defines a first inlet region configured to supplysecond cooling fluid to the second fan; and the at least one housingdefines a second inlet region configured to supply third cooling fluidto the third fan.
 34. The power-tool cooling apparatus according toclaim 33, wherein: the at least one housing defines a handle: and thesecond inlet region is defined in the handle.